BACKGROUND: Within the field of genetic schizophrenia research, eye-tracking dysfunction can be regarded as a putative trait marker in families with multiple occurrences of the disease (familial schizophrenia). We concentrated on families with single occurrences of schizophrenia (sporadic schizophrenia) to test whether a genetic factor may be present in these families as well. METHODS: Eye movements were recorded using infrared oculography in eight families with sporadic schizophrenia (44 members), eight families with familial schizophrenia (66 members), and nine nonpsychotic families (77 members). Triangle-wave stimuli at 15 degrees /sec and 30 degrees /sec were used, and gains (eye velocity/target velocity), rates, and amplitudes of saccades (classified as catch-up and anticipatory saccades) were determined. RESULTS: 1) In sporadic-schizophrenia families, gain values, saccade rates, and anticipatory saccade amplitudes at 30 degrees /sec differed in a statistically significant fashion from nonpsychotic families, but not from families with multiple occurrences of schizophrenia, and 2) at 30 degrees /sec, a significant effect of target direction on smooth-pursuit maintenance was observed in both sporadic- and familial-schizophrenia families. CONCLUSIONS: Our results support the hypothesis that genetic factors may be present even in sporadic-schizophrenia families and may contribute to a more precise and biologically based definition of the schizophrenia phenotype in future molecular genetic analysis.
BACKGROUND: Within the field of genetic schizophrenia research, eye-tracking dysfunction can be regarded as a putative trait marker in families with multiple occurrences of the disease (familial schizophrenia). We concentrated on families with single occurrences of schizophrenia (sporadic schizophrenia) to test whether a genetic factor may be present in these families as well. METHODS: Eye movements were recorded using infrared oculography in eight families with sporadic schizophrenia (44 members), eight families with familial schizophrenia (66 members), and nine nonpsychotic families (77 members). Triangle-wave stimuli at 15 degrees /sec and 30 degrees /sec were used, and gains (eye velocity/target velocity), rates, and amplitudes of saccades (classified as catch-up and anticipatory saccades) were determined. RESULTS: 1) In sporadic-schizophrenia families, gain values, saccade rates, and anticipatory saccade amplitudes at 30 degrees /sec differed in a statistically significant fashion from nonpsychotic families, but not from families with multiple occurrences of schizophrenia, and 2) at 30 degrees /sec, a significant effect of target direction on smooth-pursuit maintenance was observed in both sporadic- and familial-schizophrenia families. CONCLUSIONS: Our results support the hypothesis that genetic factors may be present even in sporadic-schizophrenia families and may contribute to a more precise and biologically based definition of the schizophrenia phenotype in future molecular genetic analysis.
Authors: Margret S H Harris; Courtney L Wiseman; James L Reilly; Matcheri S Keshavan; John A Sweeney Journal: Neuropsychopharmacology Date: 2008-06-04 Impact factor: 7.853
Authors: L Elliot Hong; Kathleen A Turano; Hugh O'Neill; Lei Hao; Ikwunga Wonodi; Robert P McMahon; Amie Elliott; Gunvant K Thaker Journal: Biol Psychiatry Date: 2007-07-30 Impact factor: 13.382
Authors: R Lencer; L J Mills; N Alliey-Rodriguez; R Shafee; A M Lee; J L Reilly; A Sprenger; J E McDowell; S A McCarroll; M S Keshavan; G D Pearlson; C A Tamminga; B A Clementz; E S Gershon; J A Sweeney; J R Bishop Journal: Transl Psychiatry Date: 2017-10-24 Impact factor: 6.222